Full-auto Air Conditioner
- Connect all center panel connectors.
- Turn the ignition switch to ON position.
- Measure the voltage at each climate control unit terminal and refer to . If not as specified, inspect the parts listed under "Action" and the related wiring harness. If there is any malfunction, replace the climate control unit.
Scheme 60
| Terminal | Signal | Connected to | Test condition | Voltage (V) | Action |
|---|---|---|---|---|---|
| 1A | Air mix 1 | Air mix actuator | Moving to HOT | (Scheme 62) | Inspect for continuity or short circuit (Climate control unit-air mix actuator: 1A-F) Inspect air mix actuator |
| Moving to COLD | |||||
| 1B | Air mix 2 | Air mix actuator | Moving to HOT | (Scheme 62) | Inspect for continuity or short circuit (Climate control unit-air mix actuator: 1B-A) Inspect air mix actuator |
| Moving to COLD | |||||
| 1C | PWM output | PWM unit | Fan speed: 1-7 | (Scheme 61) | Inspect for continuity or short circuit (Climate control unit-PWM unit: 1C-2A) Inspect PWM unit |
| 1D | Air mix 3 | Air mix actuator | Moving to HOT | (Scheme 62) | Inspect for continuity or short circuit (Climate control unit-air mix actuator: 1D-D) Inspect air mix actuator |
| Moving to COLD | |||||
| 1E | Rear window defroster SW signal | Rear window defroster relay | Rear window defroster switch is off | 12 | Inspect for continuity or short circuit (Climate control unit-rear window defroster relay: 1E-E) Inspect rear window defroster relay |
| Rear window defroster switch is on | Below 1.0 | Inspect terminal voltage of climate control unit (2H, 2L) Inspect center panel | |||
| 1F | On-board diagnostic signal | DLC | Terminal A of DLC is shorted. | Below 1.0 | Inspect for continuity (Climate control unit-DLC: 1F-A) |
| Other | 5 | Inspect short circuit (Climate control unit-DLC: 1F-A) Inspect terminal voltage of climate control unit (2H, 2L) | |||
| 1G | |||||
| 1H | |||||
| 11 | GND | Passenger compartment temperature sensor Evaporator temperature sensor Ambient temperature sensor Water temperature sensor Solar radiation sensor Airflow mode actuator | Under any condition | Below 1.0 | Inspect terminal voltage of climate control unit (2L) |
| 1J | Air mix 4 | Air mix actuator | Moving to HOT | (Scheme 62) | Inspect for continuity or short circuit (Climate control unit-air mix actuator: 1J-C) Inspect air mix actuator |
| Moving to COLD | |||||
| 1K | Ambient temperature sensor input | Ambient temperature sensor | Depends on temperature surrounding sensor | (Scheme 64) | Inspect for continuity (Climate control unit-ambient temperature sensor: 1K-B, 1I-A) Inspect for short circuit (Climate control unit-ambient temperature sensor: 1K-B) Inspect ambient temperature sensor Inspect terminal voltage of climate control unit (2H, 2L) |
| 1L | |||||
| 1M | Passenger compartment temperature sensor input | Passenger compartment temperature sensor | Depends on temperature surrounding sensor | (Scheme 65) | Inspect for continuity (Climate control unit-passenger compartment temperature sensor: 1M-B, 1I-A) Inspect for short circuit (Climate control unit-passenger compartment temperature sensor: 1M-B) Inspect passenger compartment temperature sensor Inspect terminal voltage of climate control unit (2H, 2L) |
| 1N | |||||
| 1O | Water temperature sensor input | Water temperature sensor | Depends on temperature surrounding sensor | (Scheme 66) | Inspect for continuity (Climate control unit-water temperature sensor: 10-A, 1I-B) Inspect for short circuit (Climate control unit-water temperature sensor: 1O-A) Inspect water temperature sensor Inspect terminal voltage of climate control unit (2H, 2L) |
| 1P | A/C | Refrigerant pressure switch | Fan switch at OFF | 12 | Inspect for continuity or short circuit (Climate control unit-refrigerant pressure switch: 1P-C) (Refrigerant pressure switch-PCM: B-1AC (L3), 41 (AJ)) Inspect refrigerant pressure switch Inspect PCM terminal voltage (1AC (L3), 41 (AJ)) See PCM INSPECTION [L3]. See PCM INSPECTION [AJ]. |
| Fan switch at 1st position, A/C switch ON | Below 1.0 | Inspect terminal voltage of climate control unit (2H, 2L) | |||
| 1Q | Evaporator temperature sensor input signal | Evaporator temperature sensor | Depends on temperature surrounding sensor | (Scheme 63) | Inspect for continuity (Climate control unit-evaporator temperature sensor: 1Q-A, 1I-B) Inspect for short circuit (Climate control unit-evaporator temperature sensor: 1Q-A) Inspect evaporator temperature sensor Inspect terminal voltage of climate control unit (2H, 2L) |
| 1R | |||||
| 1S | Solar radiation sensor input | Solar radiation sensor | Fluorescent light directly on the solar radiation sensor | 4.5 | Inspect for continuity or short circuit (Climate control unit-solar radiation sensor: 1S-B, 2C-A) Inspect terminal voltage of climate control unit (2C) Inspect solar radiation sensor |
| Light to solar radiation sensor block | Below 1.0 | ||||
| 1T | GND | Ground | Under any condition | Below 1.0 | Inspect for continuity (Climate control unit-ground: 1T-GND) Inspect center panel |
| 1U | Potentiometer signal | Airflow mode actuator | VENT mode | 4.1 | Inspect for continuity or short circuit (Climate control unit-airflow mode actuator: 1W-C) Inspect airflow mode actuator Inspect terminal voltage of climate control unit (2C) |
| BI-LEVEL mode | 3.3 | ||||
| HEAT mode | 2.3 | ||||
| HEAT/DEF mode | 1.5 | ||||
| DEFROSTER mode | 0.9 | ||||
| 1V | |||||
| 1W | |||||
| 1X | Hazard warning SW signal | Hazard warning switch | Hazard warning switch is off | 12 | Inspect for continuity or short circuit (Climate control unit-flasher unit: 1X-H) Inspect flasher unit |
| Hazard warning switch is on | Below 1.0 | Inspect terminal voltage of climate control unit (1T) Inspect center panel | |||
| 2A | Panel light control signal | Panel light control switch | Headlight switch ON and panel light control switch at max. illumination | 0.2 | Inspect for continuity (Climate control unit-panel light control switch: 2A-C) (Panel light control switch-ground: C-GND) Inspect panel light control switch |
| Headlight switch ON and panel light control switch at min. illumination | 10.2 | Inspect for short circuit (Climate control unit-panel light control switch: 2A-C) | |||
| 2B | TNS signal | TNS relay | Headlight switch OFF | Below 1.0 | Inspect for short circuit (Climate control unit-TNS relay: 2B-D) Inspect TNS relay Inspect headlight switch |
| Headlight switch ON | 12 | Inspect for continuity or short circuit (Climate control unit-TNS relay: 2B-D) Inspect TNS relay Inspect headlight switch | |||
| 2C | +5V | Airflow mode actuator | Ignition switch at ON position | 5 | Inspect for short circuit (Climate control unit-airflow mode actuator: 2C-B, B, A) Inspect air mix actuator Inspect airflow mode actuator Inspect solar radiation sensor Inspect terminal voltage of climate control unit connector (2H, 2L) |
| Ignition switch at LOCK position | Below 1.0 | Replace climate control unit | |||
| 2D | |||||
| 2E | Motor drive signal | Airflow mode actuator | Moving to DEFROSTER | 12 | Inspect for continuity or short circuit (Climate control unit-airflow mode actuator: 2E-F, 2G-D) Inspect airflow mode actuator |
| Moving to VENT | Below 1.0 | ||||
| 2F | Backup power supply | ROOM 15 A fuse | Under any condition | B+ | Inspect for continuity or short circuit (Climate control unit-fuse: 2F-ROOM 15 A fuse) Inspect ROOM 15 A fuse |
| 2G | Motor drive signal | Airflow mode actuator | Moving to VENT | 12 | Inspect for continuity or short circuit (Climate control unit-airflow mode actuator: 2G-D, 2E-F) Inspect airflow mode actuator |
| Moving to DEFROSTER | Below 1.0 | ||||
| 2H | IG2 | A/C 15 A fuse | Ignition switch at ON position | B+ | Inspect for continuity or short circuit (Climate control unit-fuse: 2H-A/C 15 A fuse) Inspect A/C 15 A fuse |
| Ignition switch at LOCK position | Below 1.0 | Inspect for short circuit (Climate control unit-fuse: 2H-A/C 15 A fuse) | |||
| 2I | Motor drive signal | Air intake actuator | Moving to RECIRCULATE | 12 | Inspect for continuity or short circuit (Climate control unit-air intake actuator: 2I-F, 2K-D) Inspect air intake actuator |
| Moving to FRESH | Below 1.0 | ||||
| 2J | |||||
| 2K | Motor drive signal | Air intake actuator | Moving to FRESH | 12 | Inspect for continuity or short circuit (Climate control unit-air intake actuator: 2K-D, 2I-F) Inspect air intake actuator |
| Moving to RECIRCULATE | Below 1.0 | ||||
| 2L | GND | Ground | Under any condition | Below 1.0 | Inspect for continuity (Climate control unit-ground: 2L-GND) |
CLIMATE CONTROL UNIT TERMINALS VOLTAGE REFERENCE
Scheme 61
Scheme 62
Scheme 63
Scheme 64
Scheme 65
Scheme 66
Scheme 67
Scheme 68
- Remove the climate control unit.
- Inspect for continuity between the fan switch terminals using an ohmmeter. If not as specified, replace the fan switch.
Scheme 69
Scheme 70
- Remove the climate control unit.
- Inspect for continuity between the mode switch terminals using an ohmmeter. If not as specified, replace the climate control unit.
- Verify that the resistance between the terminals of the mode switch is as shown in the table. If not as specified, replace the mode switch. MODE SWITCH RESISTANCE SPECIFICATIONS Terminals Resistance (ohm) VENT BI-LEVEL HEAT HEAT/DEF DEFROSTER A-B 0 2.48 4.96 7.44 9.92 B-D 9.92 7.44 4.96 2.48 0
Scheme 71
- Set the temperature control dial to max hot.
- Set the air mix link to max hot in the direction shown by the arrow and insert a screwdriver at the set hole.
- Connect the air mix wire to the air mix link.
- Clamp the air mix wire to the wire clamp.
- Verify that the temperature control dial rotates at full stroke.